Dual ball valve air vent valve

ABSTRACT

A unitary valve housing has an upper and lower portion. The upper portion has an inner chamber for accommodating two spaced apart balls and a cylindrical side skirt with oppositely positioned openings. The lower portion is cylindrical in shape and has a top shelf with adjacent circular openings for seating the two balls and openings communicating with a bottom of the lower portion. The two openings on the upper portion side skirt are aligned with oppositely positioned openings in a side of the lower housing. A secondary shelf is located in the lower housing below each of the two circular openings contiguous with the side openings. A lower end of the lower housing portion is attached to a conduit.

BACKGROUND OF THE INVENTION

The present invention relates to air vent valves to relieve a vacuumdeveloped in conduits. More particularly, it refers to a dual ball valvefor vacuum relief of domestic sewage piping systems in residential,commercial, industrial and institutional buildings.

A single ball valve air vent is described in U.S. Pat. No. 6,234,198.Such a valve has received widespread commercial acceptance and isadequate to carry out its intended purpose. However, for large sewerpipes with drainage from multiple commodes a single air flow channel maynot be adequate. For this reason the search continues for more efficientair flow in air vent valves.

SUMMARY OF THE INVENTION

The present invention solves the problem of adequate air flow byproviding a self contained spaced apart dual ball air vent valve thatcan be used with large sewer pipe systems to prevent sewer gasemissions.

The cylindrical valve of this invention is attached at a lower portionby threads or a press fit into a conduit, usually one employed incarrying commode fluids. The valve has an upper and lower housing. Theupper housing has a dome accommodating a pair of spaced apart balls inan inner chamber and a cylindrical skirt depending downwardly below thedome. A pair of oppositely positioned side openings penetrate the skirt.The lower housing of the valve has an upper shelf with two circularopenings penetrating the shelf to accommodate a seating of the balls bygravity. The two circular openings lead to a lower shelf which hasaccess to ambient air by alignment of oppositely positioned sideopenings with the openings in the overlapping upper housing skirt. Theupper shelf has additional openings leading to the bottom of the valvebut sealed apart from the side openings in the lower housing portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is best understood by those having ordinary skill in theart by reference to the following detailed description when consideredin conjunction with the accompanying drawings in which:

FIG.1 is a perspective view of the dual ball air vent valve mounted on aconduit.

FIG. 2 is a perspective view of the dual ball air vent valve prior tobeing press fit on a conduit.

FIG. 3 is a perspective view of the dual ball air vent valve prior tobeing threaded on a conduit.

FIG. 4 is an exploded view of the elements of the dual ball air ventvalve.

FIG. 5 is a cross sectional view along line 5-5 of FIG. 2 with the twoballs shown seated.

FIG. 6 is a cross sectional view along line 5-5 of FIG. 2 with the twoballs shown unseated.

FIG. 7 is a cross sectional view along line 7-7 of FIG. 2 with the ballshown seated.

FIG. 8 is a cross sectional view along line 7-7 of FIG. 2 with the ballshown unseated.

DETAILED DESCRIPTION OF THE BEST MODE

Throughout the following detailed description, the same referencenumerals refer to the same elements in all figures.

Referring to FIG. 1-4, the dual ball air vent valve 10 or 10 a of thisinvention is mounted on a conduit 12 or 12 a respectively depending onwhether the valve 10 is press fit on conduit 12 or valve 10 a isthreaded to conduit 12 a. In the case of valve 10 a, threads 14 on abottom portion of the valve lower housing 16 a are threadably engaged tothreads 18 on an inside surface of a conduit collar 20. Valve 10 ispress fit into conduit collar 20.

The valve 10 or 10 a has an upper housing 22 heat welded to lowerhousing 16 or 16 a. The upper housing 22 has a kidney shaped dome 24with interior chamber pockets 26 and 28 as seen in FIGS. 5-6. Pockets 26and 28 are adapted to receive balls 30 and 32 respectively andaccommodate such balls if projected upwardly from O-rings 34 and 36respectively. A separating shaft 38 prevents balls 30 and 32 fromtouching each other. Vent slots 40 and 41 are aligned with openings 52and 54 respectively, in the lower housing 16. Skirt 23 having acylindrical configuration overlaps a top portion of the lower housing.

Lower housing 16 or 16 a has a left side opening 42 and a right sideannular opening 44 depending downwardly from top shelf 46 to a lowerlevel shelf 48 and 50 respectively. A wall 60 shown in FIGS. 5 to 8separate openings 52 and 54. Vent slots 40 and 41 from upper housing 22enclose side openings 52 and 54 respectively. Sealing gaskets or O-rings34 and 36 outline openings 42 and 44 respectively and provide a tightseal with the seated balls. Vent slots 56 and 58 in top shelf 46 providethe entrance way for air flow to move downwardly into the lower housing16 or 16 a interior to conduit 12 or 12 a to relieve a vacuum in conduit12 or 12 a. Air flow as shown in FIG. 8 relieves a vacuum in conduit 12or 12 a.

Air pressure in the conduit 12 or 12 a rising through slotted openings56 and 58 cause the balls 30 and 32 to seat snugly on O-rings 34 and 36respectively as seen in FIGS. 5 and 7. If air pressure drops in theconduit as with a vacuum, the ambient air flowing through openings 40,41, 52 and 54 pushes the balls upwardly as seen in FIGS. 6 and 8 toequalize pressure in the conduit 12 or 12 a. As soon as pressure isequalized the balls 30 and 32 reseat on the O-rings 34 and 36respectively by gravity.

The valve of this invention can be made from a polymer or stainlesssteel. If made from a polymer, the preferred ones are ABS, butylstyrene, polyester, polypropylene, polyethelenetrepthalate and fireresistant polycarbonate. The balls are made of a light weight plastic.

The valve 10 or 10 a of this invention keeps sewer gases out ofhabitable places, allows more air flow than previously employed valves,can be used with large size sewer pipes and allows for drainage frommultiple commodes.

The polymeric upper housing 22 and lower housing 16 are preferably heatsealed together but also can be attached by glue, spin welding or byultra sonic welding. Stainless steel housing components are weldedtogether by conventional techniques.

Equivalent elements can be substituted for the elements set forth aboveto provide substantially the same functional valve, in substantially thesame way to provide substantially the same results.

1. A dual ball air vent valve connectable to a conduit to provide vacuumand pressure relief, the valve comprising: a unitary generallycylindrical structure having an upper and lower housing joined together,the upper structure having a dome adapted to receive two balls in aninner chamber, the balls spaced apart by a separating shaft in the innerchamber; the upper housing having a cylindrical skirt below the dome,the skirt outlining the outer periphery of the upper housing and havingtwo oppositely positioned openings in the skirt; the lower housinghaving a first shelf penetrated by two oppositely positioned circularopenings adapted to seat the two circular members and another openingadapted to permit passage of a fluid from a bottom of the lower housing;and the lower housing having a second shelf below each circular openingcommunicating with an opening on each side of the lower housing adaptedto permit the flow of air into a space below each ball so that whenconnected to a conduit at a lower end of the lower housing the valveballs will raise up when a vacuum prevails within the conduit and atzero pressure differential will seat and prevent the side opening in thelower housing from receiving a vapor from the conduit.
 2. The dual ballair vent valve according to claim 1 wherein an O-ring surrounds eachcircular opening in the lower housing first shelf and is adapted to seatthe ball.
 3. The dual ball air vent valve according to claim 2 whereinthe ball is a lightweight plastic circular member.
 4. The dual ball airvent valve according to claim 1 wherein a wall separates the openings inthe second shelf of the lower housing.
 5. The dual ball air vent valveaccording to claim 1 wherein the upper housing dome is kidney shaped. 6.The dual ball air vent valve according to claim 1 wherein the twooppositely positioned openings in the upper housing skirt consist ofmultiple spaced apart slots.
 7. The dual ball air vent valve accordingto claim 1 wherein the first shelf in the lower housing has multiplespaced part slots as the another opening.
 8. The dual ball air ventvalve according to claim 6 wherein the two oppositely positionedopenings in the upper housing skirt are aligned respectively with theopenings on each side of the lower housing when the skirt overlaps a topportion of the lower housing.
 9. The dual ball air vent valve accordingto claim 1 wherein the lower housing is threadably connected to theconduit.
 10. The dual ball air vent valve according to claim 1 whereinthe lower housing is press fit into the conduit.
 11. A dual ball airvent valve connectable to a sewer conduit, the valve comprising: anupper and lower housing sealed together; the upper housing having a domeadapted to receive the dual balls in an inner chamber, the dual ballsspaced apart in the inner chamber by a separating member; the upperhousing having a cylindrical skirt below the dome, the skirt having anannular wall forming the outer periphery of the upper housing, the wallhaving oppositely positioned openings; the lower cylindrical housinghaving an outer annular wall and a first and second shelf, the firstshelf penetrated by two oppositely positioned circular openings adaptedto seat the dual balls and another opening adapted to permit passage ofsewer gases from the conduit, the second shelf below each circularopening communicating with a side opening to an ambient air supplythrough opposite sides of the outer annular wall, the openings in theupper housing annular wall being contiguous with the side opening onopposite sides of the lower housing outer annular wall; and the lowerhousing have a bottom portion connectable to the sewer conduit.
 12. Thedual ball air vent valve according to claim 11 wherein an O-ringsurrounds each circular opening in the lower housing and is adapted toseal the ball.
 13. The dual ball air vent valve according to claim 11wherein a wall separates the openings in the opposite sides of the lowerhousing annular wall.
 14. The dual ball air vent valve according toclaim 11 wherein the upper housing dome is kidney shaped.
 15. The dualball air vent valve according to claim 11 wherein the separating memberin the inner chamber of the dome is a shaft depending from a roof of theinner chamber.
 16. The dual ball air vent valve according to claim 11wherein the lower housing is connected to the sewer conduit withthreads.
 17. The dual ball air vent valve according to claim 11 whereinthe lower housing is press fit into the sewer conduit.
 18. A dual ballair vent valve connectable to a sewer conduit, the valve comprising: anupper and lower housing sealed together; the upper housing having akidney shaped dome adapted to receive the dual balls in an innerchamber, the dual balls spaced apart in the inner chamber by a shaftdepending from a roof of the inner chamber, a cylindrical skirt belowthe dome forming an outer periphery of the upper housing, the skirtpenetrated by oppositely positioned side openings; the lower housinghaving a cylindrical shaped outer wall, a top shelf and a lower shelfbelow the top shelf, the top shelf penetrated by two adjacent circularopenings each opening containing an O-ring adapted to seat the ball andanother opening adapted to permit passage of sewer gases from theconduit; the lower housing lower shelf communicating with ambient airthrough oppositely positioned openings in the lower housing outer wall,an interior wall separating the lower shelf into two chambers, eachchamber receiving a lower portion of the ball; the oppositely positionedopenings in the upper housing skirt contiguous with the oppositelypositioned openings in the lower housing outer wall; and a lower portionof the lower housing adapted to be connected to the sewer conduit. 19.The dual ball air vent valve according to claim 18 wherein the upper andlower housing are made from a molded polymer and sealed together. 20.The dual ball air vent valve according to claim 18 wherein the upper andlower housings are made from stainless steel and are welded together.